From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932887AbWF3B7f (ORCPT ); Thu, 29 Jun 2006 21:59:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933140AbWF3B7f (ORCPT ); Thu, 29 Jun 2006 21:59:35 -0400 Received: from rgminet01.oracle.com ([148.87.113.118]:14737 "EHLO rgminet01.oracle.com") by vger.kernel.org with ESMTP id S932887AbWF3B7e (ORCPT ); Thu, 29 Jun 2006 21:59:34 -0400 Date: Thu, 29 Jun 2006 18:59:03 -0700 From: Joel Becker To: Jeff Garzik Cc: "Theodore Ts'o" , linux-kernel@vger.kernel.org Subject: Re: Proposal and plan for ext2/3 future development work Message-ID: <20060630015903.GE11640@ca-server1.us.oracle.com> Mail-Followup-To: Jeff Garzik , Theodore Ts'o , linux-kernel@vger.kernel.org References: <44A47B0D.7020308@garzik.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <44A47B0D.7020308@garzik.org> X-Burt-Line: Trees are cool. X-Red-Smith: Ninety feet between bases is perhaps as close as man has ever come to perfection. User-Agent: Mutt/1.5.11 X-Brightmail-Tracker: AAAAAQAAAAI= X-Brightmail-Tracker: AAAAAQAAAAI= X-Whitelist: TRUE X-Whitelist: TRUE Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 29, 2006 at 09:14:53PM -0400, Jeff Garzik wrote: > Agreed overall, though specifically for delayed allocation I think > that's an ext4 thing: > > * First off, I'm a big fan of delalloc, and (like extents) definitely > want to see the feature implemented > * Delayed allocation, properly done, requires careful interaction with > VM writeback (memory pressure or normal writeout), and may require some > minor changes to generic code in fs/* and mm/* To be honest, I'd like to see more delayed allocation infrastructure in the VFS itself. XFS has to maintain an entire chunk of state for it, and I suspect ext4 will as well. I'd love to get delayed allocation into OCFS2 someday. Why not move to where we can share the in-memory accounting code? Now, we'd probably want to start by prototyping it in ext4 directly. Once it's stable as a filesystem feature, we can see where XFS and ext4 overlap, etc, etc. But I'd like to keep a more generic direction in mind. Joel -- "The suffering man ought really to consume his own smoke; there is no good in emitting smoke till you have made it into fire." - thomas carlyle Joel Becker Principal Software Developer Oracle E-mail: joel.becker@oracle.com Phone: (650) 506-8127